The Imaging Core will provide resources and technologies to assess the effects of Superfund toxicants on cultured cells, tissues, and whole animals at the cellular and subcellular levels, in vivo and in vitro, by bioluminescence, confocal, and multiphoton laser light microscopies and also provide capabilities for subcellular to supramolecular imaging by advanced 3-dimensional electron microscopy. This core will leverage on the advanced instrumentation of the NCRR-supported National Center for Microscopy and Imaging Research (NCMTR), which Dr. Ellisman directs at UC San Diego. Working closely with Dr. Ellisman, Dr. Tsien will oversee the development and application of new fluorescence, biarsenical reporter, and tetracysteine-based methods for the analysis of gene and protein expression and detection both in cultured cells and tissues. The core is fully equipped with state-of-the-art instrumentation and is staffed with experienced scientists who shall assist in the development and execution of experiments. Personnel of the Imaging Core will provide training and assistance with novel labeling strategies, whole-animal imaging, immunofluorescence, in situ hybridization, EM immunolocalizations, EM tomography, and cryoelectron microscopy interfaced with 2D and 3D biological image analysis.